It's twice slower then node-sass

[FDiskas]

Please check this simple example
test.zip
Reproduce:

1. yarn
2. yarn dart
3. yarn node

Or using NPM:

1. npm install
2. npm run dart
3. npm run node

Using gnomon

Or using time

[nex3]

We're aware of the performance differences; we track performance in this file and we have #113 open to improve speed in JS. It's also worth noting a few general things about performance:

• Node Sass is a wrapper for LibSass, which is written in C. Dart Sass (as distributed on NPM) is pure JavaScript. C is almost always going to be faster than pure JavaScript. Getting within 2-3x speed is pretty impressive, all things considered.

• Running Dart Sass from Dart will also always be faster than running it from JavaScript, because the Dart VM is faster than the JavaScript VM (for various reasons that are tangential to this discussion). You can try this yourself by downloading the Dart release from the releases page.

• Our benchmarks have generally indicated that Dart Sass from Dart tends to be about the same speed or slightly faster than LibSass, due to algorithmic improvements. If speed is your primary concern and you don't need to define custom functions or importers in JavaScript, I'd recommend using that.

Addendum:

• If you're interested in a fast implementation that's easy to install via npm, I've outlined a possible plan for that in Add an embeddable execution mode #248. However, in order to make this work, I need someone who's willing to develop a JS wrapper that communicates with a Dart executable using protocol buffers or a similar high-speed protocol. If you're interested in helping out with this, comment on Add an embeddable execution mode #248.

[halfnibble]

dart-sass finally supports all the features I am using with version 1.13.2. But my Sass/CSS build must be complicated because it takes about 46 seconds, or 6.5x longer. :(

[nex3]

@halfnibble If you can provide a stylesheet that's that much slower to compile in JS than it is in the Dart VM, that would be helpful for our optimization efforts.

[FDiskas]

As a comparison I prefer to use bootstrap as example.